High Speed Counter [C]; Types And Device Numbers Of High Speed Counters - Mitsubishi FX3U Series Programming Manual

FX /FX Series Programmable Controllers
3U 3UC
Programming Manual - Basic & Applied Instruction Edition
4.7

High Speed Counter [C]

4.7.1

Types and device numbers of high speed counters

1. Types of high speed counters
The main unit has built-in 32-bit high speed bi-directional counters (1-phase 1-counting, 1-phase 2-counting
and 2-phase 2-counting). These high speed counters are classified into the hardware type or the software
type by the counting method. Some high speed counters are able to select external reset input terminal and
external start input terminal (for counting start).
2. Classification of high speed counters by the counting method
• Hardware counters: These types of counters execute counting by hardware, but are switched to software
• Software counters: These types of counters execute counting as CPU interrupt processing.
3. Types of high speed counters and input signal forms
The table below shows the types (1-phase 1-counting, 1-phase 2-counting and 2-phase 2-counting) and input
signals (waveforms) of high speed counters.
1-phase
1-counting input
1-phase
2-counting input
1 edge
count
2-phase
2-counting
input
4 edge
count
4. Cautions on counterpart equipment connected to high speed counter inputs
General-purpose inputs X000 to X007 are used for high speed counter inputs. An encoder
output method shown in the table below can be connected depending on the connected terminal.
Encoders adopting the voltage output method and absolute encoders cannot be connected to high speed
counter inputs.
Output method of encoder which can be directly connected
to input terminal in main unit
Output method of encoder which can be directly connected
to input terminal in FX
*1. A rotary encoder adopting the output method shown above may not operate correctly depending on
the electrical compatibility. Check the specifications before connecting an encoder.
88
counters depending on the operating condition.
It is necessary to use each software counter within both limitations of maximum
response frequency and total frequency.
→ For the limitation of response frequency depending on the total frequency,
Input signal form
UP/DOWN
+1 +1
UP
DOWN
A phase
+1 +1
B phase
During forward rotation
+1 +1 +1 +1 +1
A phase
B phase
+1 +1 +1 +1
During forward rotation
→ For the wiring, refer to the Hardware Manual of the main unit.
-4HSX-ADP
3U
→ For the condition handled as software counters,
+1
−1 −1 −1
A phase
−1 −1
B phase
During backward rotation
−1 −1 −1 −1 −1
A phase
B phase
−1 −1 −1 −1
During backward rotation
Open collector transistor output method compatible with 24V
DC
Differential line driver output method
(output voltage: 5V DC or less)
4 Devices in Detail
4.7 High Speed Counter [C]
refer to Subsection 4.7.9.
refer to Subsection 4.7.10.
Counting direction
Down-counting or up-counting is
specified by the ON/OFF status of
M8235 to M8245.
ON: Down-counting
OFF: Up-counting
A counter executes up-counting or
down-counting as shown on the left.
The counting direction can be
confirmed in M8246 to M8250.
ON: Down-counting
OFF: Up-counting
A counter automatically executes
up-counting or down-counting
according to changes in the input
status of the A/B phase as shown on
the left.
The counting direction can be
confirmed in M8251 to M8255.
ON: Down-counting
OFF: Up-counting
*1
adopting the